1. Field of the Invention
The present invention relates to a cleaning device for cleaning residual toner remaining on a developer image carrier and an image forming apparatus equipped with this cleaning device.
2. Description of the Related Art
As an image forming apparatus to form a toner image on a photosensitive body according to an electrophotographic system, in recent years it has been planned to put a wet type image forming apparatus using toner particles as extremely fine as sub-micron in practical use. Especially, in the case of a full-color image forming apparatus capable of obtaining a full-color toner image by superposing plural color toners has such merits as it is economical because a sufficient image density is obtained from small amounts of toners, texture comparable to printing (for example, offset printing) can be realized and further, energy saving is attained as a developer image can be fixed at relatively low temperatures, and the more practical use of a wet type image forming apparatus is expected.
However, in the case of this wet type image forming apparatus, toner particles are extremely fine and it is difficult to remove residual toners remaining on a photosensitive body or an intermediate transfer body after completing the transfer and toners tend to remain on the photosensitive body or the intermediate transfer body as toners are not completely removed. As a result, there were problems such that toners left on the photosensitive body or the intermediate transfer body were offset on a developing roller or a sheet of paper acting as a transfer paper. Also, the toners mixed in a developing device and produced developers of mixed colors or contaminated a toner image formed on a sheet paper. Further, toners adhered on the photosensitive body or the intermediate transfer body were hardened to a film shape, and produced a filming phenomenon and image void. Therefore, maintenance to remove toners adhering on the photosensitive body or the intermediate transfer body was necessitated frequently.
On the other hand, in the case of an image forming apparatus for forming a developer image on a photosensitive body according to the electrophotographic system, a technology is disclosed in Japanese Patent Publication No. 10-149033 for cleaning a photosensitive body after completing the transfer of image by an image forming apparatus equipped with a cleaning device comprising a rotary brush and a web system wiping device.
However, according to this conventional technology it was necessary to arrange cleaning devices having different functions separately around a photosensitive body after completing the transfer and a broad space was required and the realization of a small sized image forming apparatus was impeded.
Accordingly, improvement of cleaning characteristic without impeding saving of the space requirement for a cleaning device is desired for surely removing residual toner on a photosensitive body and an intermediate transfer body.
The objects of this invention are to promote cleaning characteristics of a cleaning device without impairing space saving, obtain a high quality image by preventing mixture of color developers by residual toners, contamination of images, drop of image quality in order for surely removing residual toners remaining on a photosensitive body and intermediate transfer body and reducing maintenance requirement.
According to the embodiments of this invention, there is provided a cleaning device comprising: a first cleaning member that is provided opposing to a developer image carrier for scraping the surface of the developer image carrier; and a second cleaning member that is put over the first cleaning member and runs between the surface of the developer image carrier and the first cleaning member for wiping the surface of the developer image carrier simultaneously with the scraping of the surface of the developer image carrier.
Further, according to this invention, there is provided an image forming apparatus comprising: a latent image carrier; an image forming unit to form a developer image on the latent image carrier; a transferring device to transfer the developer image formed on the latent image carrier on a transfer body; and a cleaning device that has a first cleaning member having a function to scrape the surface of the latent image carrier, a second cleaning member having a function to run between the surface of the latent image carrier and the first cleaning member for wiping the surface of the latent image carrier, and simultaneously executes the scraping by the first cleaning member and the wiping by the second cleaning member.
Further, according to another embodiment of this invention, there is provided an image forming apparatus comprising: a latent image carrier; an image forming unit to form a developer image on the latent image carrier; an intermediate transfer body to secondarily transfer the developer image that is primarily transferred from the latent image carrier to a transfer material; and a cleaning device that is provided opposing to the intermediate transfer body, has a first cleaning member having a scraping function of the surface of the intermediate transfer body and a second cleaning member having a wiping function of the surface of the intermediate transfer body by running between the intermediate transfer body surface and the first cleaning member in the state of being put over the first cleaning member and the wiping by the second cleaning member.